Topic
Spectrum analyzer
About: Spectrum analyzer is a research topic. Over the lifetime, 12217 publications have been published within this topic receiving 101851 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, a dual probe with a U-shaped loop was proposed to sense radio frequency (RF) magnetic and electric fields simultaneously, so that the one-time scanning by the dual probe can replace the two-time scan by single-detector probes.
Abstract: A near-field scanning is usually time-consuming to map the electromagnetic field along the surface of a device. In this communication, a dual probe is proposed with a U-shaped loop to sense radio frequency (RF) magnetic and electric fields simultaneously, so that the one-time scanning by the dual probe can replace the two-time scanning by single-detector probes. Different from the traditional near-field scanning by using a single-detector probe and spectrum analyzer, the proposed scanning can be achieved by the two-output probe and a two-port vector network analyzer connecting to the probe. The efficient near-field scanning measurements of the electric and magnetic field on a conductor-backed coplanar waveguide transmission line and an RF power divider by using the dual probe are in agreement with those by using two single-detector probes.
37 citations
Patent•
23 May 1985
TL;DR: In this paper, a portable spectrum analyzer using frequency synthesis is used in the field to perform voltage amplitude measurements of specified channel segments in a multichannel configured coaxial cable environment.
Abstract: A portable spectrum analyzer using frequency synthesis is used in the field to perform voltage amplitude measurements of specified channel segments in a multichannel configured coaxial cable environment The instrument is a microprocessor (28) based system, and includes an RF input (1) and keyboard (36) and function switch inputs and provides both aural and visual outputs by means of a speaker and an LCD display (27) A three stage frequency converter (7) including PLLs (11, 12 and 13) controlled by the microprocessor (28) allows for the automatic monitoring of a plurality of carrier channels or the display of both video and audio levels of a single channel Automatic adjustment of the input signal level is provided by attenuator pads (2 and 3) controlled by the microprocessor (28) Calibration is also automatically controlled by the periodic injection of a signal of predetermined level from a noise source (4) under the control of the microprocessor (28) The microprocessor is programmed to provide several modes of operation including a sweep mode, a zoom mode, and a memory mode In the sweep mode, the instrument continually scans all carrier channels automatically, each channel being presented sequentially and simultaneously in bar graph form on the LCD display (27) In the zoom mode, a single channel is displayed with both video and audio levels side by side In the memory mode, the operator can view data saved from measurements previously made at a selected location in the cable system
37 citations
Patent•
14 Jul 1971TL;DR: In this article, a magneto-optic rotation analyzer for linearly polarized light beam is described, where a magnetic field is applied to the sample parallel to the light beam to obtain the rotation of the polarization of the light.
Abstract: A magneto-optic rotation analyzer method and apparatus is disclosed. In the analyzer, a light beam of linearly polarized light, preferably in the ultra-violet region is shown through a sample of a material to be analyzed. A magnetic field is applied to the sample parallel to the light beam to obtain magneto-optic rotation of the polarization of the light by constituents of the sample. The emerging light beam is analyzed as to its polarization to separate light which is rotated from light which has not been rotated. One of the separated light beams is detected by a photodetector. The magneto-optic rotation effect is modulated at a certain modulation frequency and the output signal is synchronously detected against the modulation frequency or a harmonic thereof for improved signal-to-noise ratio. The synchronously detected output is measured to obtain a measurement of the sample under analysis.
37 citations
Patent•
27 Dec 1982TL;DR: In this paper, a link quality analyzer is used to measure the link quality between a calling station and a called station by continuously transmitting a plurality of signal tones and sample them.
Abstract: A link quality analyzer measures the link quality between a calling station and a called station by continuously transmitting a plurality of signal tones. The called station receives the plurality of transmitting tones and sample them. A power spectrum is obtained of the received tones. From the statistics of the power spectrum the parameters of signal-to-noise ratio, multipath delay spread, Doppler frequency spread, frequency offset statistics, frequency-amplitude correlation, average amplitude response versus frequency, signal fading statistics, harmonic and intermodulation distortions, RMS-to-mean signal ratio, noise profile, and various noise statistics are determined. The power spectrum of the plurality of tones is measured through the use of digital sampling techniques and digital fast Fourier transform techniques that are implemented through microprocessor-level technology.
37 citations
TL;DR: In this article, a calibration system for harmonic power analyzers and related equipment is described and a method for verifying the software based calculations of the harmonic quantities obtained with the digital recorder of the calibration system is discussed.
Abstract: The paper describes a calibration system which is being used to evaluate the performance of harmonic power analyzers and related equipment. A method for verifying the software based calculations of the harmonic quantities obtained with the digital recorder of the calibration system is discussed. Test results of a harmonic power analyzer are also included. >
37 citations